Hmm! Oh, that's interesting. I never even noticed it was that way on your site.
The good news is that... it IS there.
And what I mean by that is, inspect the html of the page once it's rendered and search for 'ddmenu'. The css file is loading, and the div that holds the navigation is, too. But if you look at the 'li' elements in the navigation, all the links inside them have the class of 'hide' on them, thus, disabling them from view.
Add this line to your css to fix this:
Code:
.ddmenu ul li a.hide {
display: block !important;
}
The !important will override the default behavior of 'hide' but only inside 'ddmenu'. It won't get rid of the class itself, but that's fine now. The javascript that controls the profile tab navigation is probably adding 'hide' to all 'li' elements except for the one belonging to the currently active tab.